Hoya Corporation

Mitsubishi Chemical Corporation

Idemitsu Kosan Company, Limited

Tsukishima Kikai Co., Ltd.

Hideki Suda

Masaru Mitsui

Kimihiro Okada

Yoshiaki Mori

Masahiko Yamagishi

Shuji Yoshida

Kazuhide Yamashiro

Toshiyuki Furuya

Go Takahashi

Kazuyuki Yoshitomi

Masahiro Kodama

Shuichi Masuda

Provided are processes for producing high-purity succinic acid from a succinic-acid-containing liquid through crystallization.

Processes for producing succinic acid

A manufacturing method of an optical element is provided, the optical element comprising: a shield part formed by a light shielding film formed and patterned on a substrate; a light transmission part formed by partially exposing a surface of the substrate; and a phase shifter part formed by partially etching the surface of the substrate, the method comprising the steps of: preparing an optical element blank with the light shielding film and a first resist film laminated on the substrate in this order; and forming a first resist pattern by applying drawing and development to the first resist film, covering a formation scheduled area of the shield part, and demarcating the formation scheduled area of the phase shifter part.

Method of manufacturing optical element, and optical element

A light-shielding layer over a transparent substrate is processed into a predetermined pattern by first etching and then a recess is formed in an underlying layer below the light-shielding layer by second etching using at least the light-shielding layer as a mask. Subsequently, a defect inspection of the recess is performed. If, as a result of the inspection, a residue defect is detected at the recess otherwise formed in the underlying layer below the light-shielding layer, defect portion data of a pattern of a region including a residue-defect portion is produced and a repairing resist pattern is formed on the light-shielding layer based on the defect portion data. Then, third etching is applied to the underlying layer below the light-shielding layer using the light-shielding layer and the repairing resist pattern as a mask, thereby repairing the residue-defect portion.

Pattern forming method and phase shift mask manufacturing method

A light-shielding film patternhaving a main openingand auxiliary openingsis formed in a first process and, then, recess etching of a transparent substrate (formation of a substrate etched portion) is performed in a second process. Thus, the main opening and auxiliary openings can be simultaneously exposed in the first process and the positioning accuracy of them becomes excellent. Patterning of a light-shielding filmis performed by the use of an etching mask layerand therefore the processing accuracy of the light-shielding film becomes excellent. The etching mask layeris removed in a third process as the final process and thus the light-shielding film patterncan be protected by the etching mask layerupon recess-etching the transparent substrate in the second process. Thus, it is possible to prevent damage to the light-shielding film patternin the recess etching of the transparent substrate. Specifically, the etching mask layeritself is damaged in the recess etching of the transparent substrate and this etching mask layeris removed in the third process, causing no problem.

Method of producing phase shift masks

A phase shift mask manufacturing method comprises the steps of processing a light-shielding layer over a transparent substrate into a predetermined light-shielding pattern, forming a resist film on the predetermined light-shielding pattern, performing writing on the resist film based on writing data and developing the resist film, thereby forming a resist pattern, and etching an underlying layer using the predetermined light-shielding pattern and the resist pattern as a mask, thereby forming recesses, that serve as phase shift portions, in the underlying layer. The writing data includes a portion where pattern data corresponding to at least the two recesses adjacent to each other through a light-shielding portion in the predetermined light-shielding pattern are combined into one pattern data.

A half tone type phase shift mask as well as a phase shift mask blank for the mask is formed with a thin film light translucent portion made of essentially, nitrogen, metal, and silicon. The containing rate of each element and ratio in the thin film is specified in a certain range to improve film characteristics, such as acid resistance, photo resistance, conductivity, refractive index rate (film thickness), light transmission rate, etching selectivity, etc. of the light translucent portion. The phase shift mask satisfies optical characteristics (i.e., light transmitting rate and phase shift amount) with high precision, as well as reduces defects in the thin film.

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Tokyo, Japan

Hideki Suda